I have owned Rock Shox, Manitou, and Fox on 8 or 9 different bikes and Fox (i know it was not one of your choices) is my favorite. The travel seems to be far mor linear than Rock in particular. Also, in order to fully utilize all of the travel the fork or shock has, you are instructed by Fox to have it bottom out on what you would consider your most agressive manuver (I bottom out about once in 10 or so rides). The other manufacturers do not suggest setting their products this way so in essence a 4in travel fork becomes a 3.5 etc. Fox´s suggestion to set them this way to me means they are pretty confident in their workmanship.
Strong vote for Fox here.